Full load current calculator
Calculate the full load current of motors or electrical equipment from power, voltage, and power factor. Works for single-phase and three-phase systems.
full load current calculator
Full load current is the current taken up when electrical equipment is at full load capacity. To determine amps use the right equation either of a single phase or three phase.
Formula & Table Summary:
Energy (Wh): Wh = P_load × t
Ah from Wh: Ah = Wh ÷ V
Required Ah: Ah_req = (P_load × t) ÷ (V × DoD × η)
Runtime: t = (Ah_bat × V × DoD × η) ÷ P_load
battery storage kWh calculator
A battery capacity calculator is useful to calculate the size of a battery (in ampere-hours, Ah, or watt-hours, WH) required to provide power to an object over a specific time. Entering load power, runtime, voltage, depth of discharge (DoD), and efficiency will compute the size of the required battery. The equations give a relationship between Wh and Ah of battery storage. The tool can be effective in sizing batteries used in solar, backup, UPS, EV, or off-grid applications.
battery capacity calculator
| Scenario | Inputs | Result |
|---|---|---|
| Lamp 60W, 10h | 12V, DoD 50%, η 95% | Ah_req ≈ 105 → 120 Ah |
| Backup 300W, 4h | 24V, DoD 80%, η 90% | Ah_req ≈ 69 → 75 Ah |
| Solar 1kW, 2h | 48V, DoD 60%, η 88% | Ah_req ≈ 79 → 80–100 Ah |
| EV 20 kWh | 400V, DoD 90%, η 90% | Ah_req ≈ 62 Ah pack |
Frequently Asked Questions - Full load current calculator:
What is full load current?
It is the current drawn when a motor or equipment operates at its rated load.
How do I calculate full load current for a single-phase motor?
I = (P*1000)/(V*PF).
How do I calculate full load current for a three-phase motor?
I = (P*1000)/(√3*V*PF).
Does power factor affect full load current?
Yes, lower PF increases current draw.
Can I use HP instead of kW?
Yes, convert HP to kW by multiplying by 0.746.
Why is my motor drawing more current than calculated?
Possible causes include overload, low voltage, or mechanical issues.
Can I use this for generators?
Yes, if you know rated power, voltage, and power factor.
What is the importance of FLC?
It ensures correct breaker, fuse, and wire sizing.
Does efficiency affect FLC?
Yes, lower efficiency increases input power and current.
Is FLC same as starting current?
No, starting current is much higher than FLC.
